Fix empty titles on pages without application names

Summary: Fixes T3195. Currently, we show [] Phabricator on the homepage with unicode glyphs off.

Test Plan:
Viewed home page and application pages with glyphs on and off. Saw:

Reviewers: btrahan, chad

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T3195

Differential Revision: https://secure.phabricator.com/D5932